The use of digital image-forming apparatuses such as, for example, thermal ink-jet printers, large-format plotters, piezo-electric printers, laser printers, silver halide grade photo imaging apparatuses, and others has grown in recent years. The growth may be attributed to substantial improvements in print resolution and overall print quality coupled with appreciable reduction in cost, and ease of use. Today's image-forming apparatuses offer acceptable print quality for many commercial, business, and household applications at costs lower than that offered in the past.
Perceived color quality can be quantified using any one of several color space systems, such as CIELAB or Munsell, as is well known in the art. With respect to Munsell color space, a given color is defined using three terms, namely Hue, Value, and Chroma. With respect to CIELAB color space, a color is defined using three terms L*, a*, and b*. With this system, L* defines the lightness of a color, and it ranges from 0 to 100 (with 100 being white). Additionally, the terms a* and b*, together, define the hue, where a* ranges from a negative number (green) to a positive number (red), and b* ranges from a negative number (blue) to a positive number (yellow). Additional terms such as h° (hue angle) and C* (chroma) are used to further describe a given color, as is known to those skilled in the art.
In general, a successful ink for color ink-jet printing has the following properties: good crusting resistance, good stability, appropriate viscosity and surface tension, rapid dry time, and/or consumer-safety. When placed into a thermal ink-jet system, the ink set should also be kogation-resistant. However, a single ink-jet ink which has good chroma, gamut, hue angle, and environmental robustness (e.g., air fastness, light fastness, water fastness) is not always optimal for use with other inks with which it is used in combination. In other words, not only does an individual ink (e.g., cyan, magenta, or yellow ink), have to independently have acceptable color qualities, but it should also work well when used as part of an ink set.
Accordingly, it would be desirable to provide inks for use in ink-jet printing, which when used individually as well as in combination with other inks, have acceptable print quality, reliability performance, and/or environmental robustness.